1. Field of the Invention
The present invention relates to an information storage apparatus having a capability of saving data and an article of manufacture.
2. Description of the Related Art
Conventionally, examples of the information storage apparatus include a digital camera, a digital video recorder, a digital sound recorder, etc. A storage medium used for the information storage apparatus has a limited capacity. An available free space may be insufficient when new digital data needs to be saved. If the storage medium is removable, such as a floppy disk, a memory card, etc., it just needs to be replaced with a new one. Even if the storage medium is not removable, such as a hard disk, it is possible to transfer part or all of the saved data to other apparatuses. When data is transferred to other apparatuses, that data is not lost. It is possible to increase a free space by deleting the transferred data. However, for example, if other apparatuses are not available at a place where one has gone, or if transfer means is not available, it is necessary to delete part or all of the currently saved data. There is no problem in deleting data if it is unnecessary. However, it is difficult to determine data to be deleted in a short time. There have been cases where necessary data is deleted inadvertently. Further, it has been difficult to easily estimate how much free space is made available by deletion of the data.
The conventional information storage apparatus has the following drawback. Namely, when the storage medium is not removable or data cannot be transferred to other apparatuses, if there is insufficient free space, some data must be deleted when storing new data.